I looked in how to and diys can't find anything on how to do a timing chain tensioner

I recommend Cloyes timing sets. get both sets one for the cams the other for the ballance shafts. Have the water pump on will call as it is chain driven.

Cloyes has a quick DIY on You tube that gives a decent overview. of-corse the engine is on a stand not in a car.
Toughest part is getting to the chain with all the plastic, tin and brackets in the way of the engine.
Most shops quote anywhere between 6 and 8 hours, If have the right tools and are comfortable working with them, You have all the parts, and possibly a helper its doable in one day. Otherwise plan a weekend.

+1 on the Cloyes set. Changed mine out a couple of months ago. Not too bad of a job. Water pump was probably the biggest pain.

I think OP only wants to change the tensioner for the revised version. This is a fairly simple job if the old tensioner hasn't fallen apart. You take the valve cover off, tightly zip tie the chain to the cam gears. The next step is where you might need a third hand if the tensioner has fallen apart like they often do. My 08 had fallen apart, so you have to apply pressure on the plastic guide opposite the tensioner as you unscrew it so no parts fall inside the chain cover. If your lucky enough and it hasn't come apart like my 07 it will come right out intact. Then just screw in the new one in, torque to spec and tap the guide to release the tensioner plunger, remove zip-ties and re-install cover and you should be good to go.

Thanks Colby that's what I want to do so I don't have a problem later

Hi Coby; I'm going to be looking at the tensioner on this Cobalt I bought my son tomorrow and I may just go ahead and replace it since I'll have the valve cover off anyway (oil leaking around the cover). Does the tensioner get mounted near the top of the engine? I wish there were some pictures available of this process. I'm surprised no one has done a DIY for this job... Can't seem to find any YT videos either.

Thanks in advance for the assistance.

It's near the top left of the engine, it's a 32mm head jutting out the back of the engine.

I see now... Thanks very much!

Yeah, this should be an easy one. So, if the head on the tensioner has a bump on it, it's the new style tensioner, but I really still don't know how long it's been installed. The car is at 176K and it's been maintained fairly well. Tomorrow will be the first opportunity for me to really take a look at it..

Cold starts are silent currently, but for the 35 bucks the tensioner costs, and since I'll be in there anyway, I'm thinking it'll be good peace of mind..

Went very easily. I got the old one out, and it was the old style with the spring. It looked fairly warn, but was not broken. The new one went in without a hitch.

Sometimes we get lucky!!!